Injection drug use and Hepatitis C as risk factors for mortality in HIV-infected individuals: The Antiretroviral Therapy Cohort Collaboration. JAIDS
May et al. on behalf of the Antiretroviral Therapy Cohort Collaboration aimed to determine whether the association between intravenous drug use (IDU) and mortality is explained by differential rates of hepatitis C virus (HCV) infection. The prevalence of HCV among IDU was 85%. Mortality hazard ratio (HR) for both IDU and HCV were similar and substantially elevated. For most causes of death, mortality was higher in IDU compared with non-IDU and in HCV+ compared with HCV-. The association of transmission through IDU with all-cause mortality was attenuated after adjustment for HCV coinfection, but mortality remained more than 50% higher in IDU than in non-IDU.
In conclusion, a substantial proportion of the excess mortality in HIV-infected IDU is explained by HCV coinfection. The analyses underscore the importance of treating HCV coinfection among those living with HIV, many of whom no longer use injection drugs but are continuing to suffer consequences of past use.